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<a href="port__space_8hpp.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno">    1</span><span class="comment">/* Flow</span></div>
<div class="line"><a id="l00002" name="l00002"></a><span class="lineno">    2</span><span class="comment"> * Copyright 2023 Akamai Technologies, Inc.</span></div>
<div class="line"><a id="l00003" name="l00003"></a><span class="lineno">    3</span><span class="comment"> *</span></div>
<div class="line"><a id="l00004" name="l00004"></a><span class="lineno">    4</span><span class="comment"> * Licensed under the Apache License, Version 2.0 (the</span></div>
<div class="line"><a id="l00005" name="l00005"></a><span class="lineno">    5</span><span class="comment"> * &quot;License&quot;); you may not use this file except in</span></div>
<div class="line"><a id="l00006" name="l00006"></a><span class="lineno">    6</span><span class="comment"> * compliance with the License.  You may obtain a copy</span></div>
<div class="line"><a id="l00007" name="l00007"></a><span class="lineno">    7</span><span class="comment"> * of the License at</span></div>
<div class="line"><a id="l00008" name="l00008"></a><span class="lineno">    8</span><span class="comment"> *</span></div>
<div class="line"><a id="l00009" name="l00009"></a><span class="lineno">    9</span><span class="comment"> *   https://www.apache.org/licenses/LICENSE-2.0</span></div>
<div class="line"><a id="l00010" name="l00010"></a><span class="lineno">   10</span><span class="comment"> *</span></div>
<div class="line"><a id="l00011" name="l00011"></a><span class="lineno">   11</span><span class="comment"> * Unless required by applicable law or agreed to in</span></div>
<div class="line"><a id="l00012" name="l00012"></a><span class="lineno">   12</span><span class="comment"> * writing, software distributed under the License is</span></div>
<div class="line"><a id="l00013" name="l00013"></a><span class="lineno">   13</span><span class="comment"> * distributed on an &quot;AS IS&quot; BASIS, WITHOUT WARRANTIES OR</span></div>
<div class="line"><a id="l00014" name="l00014"></a><span class="lineno">   14</span><span class="comment"> * CONDITIONS OF ANY KIND, either express or implied.</span></div>
<div class="line"><a id="l00015" name="l00015"></a><span class="lineno">   15</span><span class="comment"> * See the License for the specific language governing</span></div>
<div class="line"><a id="l00016" name="l00016"></a><span class="lineno">   16</span><span class="comment"> * permissions and limitations under the License. */</span></div>
<div class="line"><a id="l00017" name="l00017"></a><span class="lineno">   17</span><span class="comment"></span> </div>
<div class="line"><a id="l00018" name="l00018"></a><span class="lineno">   18</span><span class="comment">/// @file</span></div>
<div class="line"><a id="l00019" name="l00019"></a><span class="lineno">   19</span><span class="comment"></span><span class="preprocessor">#pragma once</span></div>
<div class="line"><a id="l00020" name="l00020"></a><span class="lineno">   20</span> </div>
<div class="line"><a id="l00021" name="l00021"></a><span class="lineno">   21</span><span class="preprocessor">#include &quot;<a class="code" href="detail_2net__flow__fwd_8hpp.html">flow/net_flow/detail/net_flow_fwd.hpp</a>&quot;</span></div>
<div class="line"><a id="l00022" name="l00022"></a><span class="lineno">   22</span><span class="preprocessor">#include &quot;<a class="code" href="net__flow__fwd_8hpp.html">flow/net_flow/net_flow_fwd.hpp</a>&quot;</span></div>
<div class="line"><a id="l00023" name="l00023"></a><span class="lineno">   23</span><span class="preprocessor">#include &quot;<a class="code" href="net__flow_2error_2error_8hpp.html">flow/net_flow/error/error.hpp</a>&quot;</span></div>
<div class="line"><a id="l00024" name="l00024"></a><span class="lineno">   24</span><span class="preprocessor">#include &quot;<a class="code" href="log_8hpp.html">flow/log/log.hpp</a>&quot;</span></div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno">   25</span><span class="preprocessor">#include &quot;<a class="code" href="random_8hpp.html">flow/util/random.hpp</a>&quot;</span></div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno">   26</span><span class="preprocessor">#include &lt;boost/dynamic_bitset.hpp&gt;</span></div>
<div class="line"><a id="l00027" name="l00027"></a><span class="lineno">   27</span><span class="preprocessor">#include &lt;boost/utility.hpp&gt;</span></div>
<div class="line"><a id="l00028" name="l00028"></a><span class="lineno">   28</span><span class="preprocessor">#include &lt;boost/random.hpp&gt;</span></div>
<div class="line"><a id="l00029" name="l00029"></a><span class="lineno">   29</span><span class="preprocessor">#include &lt;queue&gt;</span></div>
<div class="line"><a id="l00030" name="l00030"></a><span class="lineno">   30</span> </div>
<div class="line"><a id="l00031" name="l00031"></a><span class="lineno">   31</span><span class="keyword">namespace </span><a class="code hl_namespace" href="namespaceflow_1_1net__flow.html">flow::net_flow</a></div>
<div class="line"><a id="l00032" name="l00032"></a><span class="lineno">   32</span>{</div>
<div class="line"><a id="l00033" name="l00033"></a><span class="lineno">   33</span><span class="comment"></span> </div>
<div class="line"><a id="l00034" name="l00034"></a><span class="lineno">   34</span><span class="comment">/**</span></div>
<div class="line"><a id="l00035" name="l00035"></a><span class="lineno">   35</span><span class="comment"> * Internal `net_flow` class that maintains the available Flow-protocol port space, somewhat similarly to the</span></div>
<div class="line"><a id="l00036" name="l00036"></a><span class="lineno">   36</span><span class="comment"> * classic TCP or UDP port scheme.  The class&#39;s main use case it to be stored in a Node, though it</span></div>
<div class="line"><a id="l00037" name="l00037"></a><span class="lineno">   37</span><span class="comment"> * could be used in other scenarios of desired.  `net_flow` users should not use this class directly.</span></div>
<div class="line"><a id="l00038" name="l00038"></a><span class="lineno">   38</span><span class="comment"> *</span></div>
<div class="line"><a id="l00039" name="l00039"></a><span class="lineno">   39</span><span class="comment"> * The port scheme is similar to TCP or UDP&#39;s but not identical.  net_flow::flow_port_t maximum value</span></div>
<div class="line"><a id="l00040" name="l00040"></a><span class="lineno">   40</span><span class="comment"> * defines the total number of ports available.  Port #S_PORT_ANY is a special value and cannot be</span></div>
<div class="line"><a id="l00041" name="l00041"></a><span class="lineno">   41</span><span class="comment"> * used as a port.  The remaining port space is divided into 2 parts: #S_NUM_SERVICE_PORTS &quot;service</span></div>
<div class="line"><a id="l00042" name="l00042"></a><span class="lineno">   42</span><span class="comment"> * ports&quot; and #S_NUM_EPHEMERAL_PORTS &quot;ephemeral ports.&quot;  Thus the port ranges are</span></div>
<div class="line"><a id="l00043" name="l00043"></a><span class="lineno">   43</span><span class="comment"> * [`S_FIRST_SERVICE_PORT`, `S_FIRST_SERVICE_PORT + S_NUM_SERVICE_PORTS - 1`] and</span></div>
<div class="line"><a id="l00044" name="l00044"></a><span class="lineno">   44</span><span class="comment"> * [`S_FIRST_EPHEMERAL_PORT`, `S_FIRST_EPHEMERAL_PORT + S_NUM_EPHEMERAL_PORTS - 1`], respectively.  Both</span></div>
<div class="line"><a id="l00045" name="l00045"></a><span class="lineno">   45</span><span class="comment"> * types of ports are on the same number line so that Flow-protocol socket addressing can be symmetrical</span></div>
<div class="line"><a id="l00046" name="l00046"></a><span class="lineno">   46</span><span class="comment"> * between client and server once a connection has been set up.</span></div>
<div class="line"><a id="l00047" name="l00047"></a><span class="lineno">   47</span><span class="comment"> *</span></div>
<div class="line"><a id="l00048" name="l00048"></a><span class="lineno">   48</span><span class="comment"> * At construction all ports are available.  A port can then be &quot;reserved&quot; by the class user.  That</span></div>
<div class="line"><a id="l00049" name="l00049"></a><span class="lineno">   49</span><span class="comment"> * port can then no longer be reserved until it is &quot;returned&quot; via return_port().</span></div>
<div class="line"><a id="l00050" name="l00050"></a><span class="lineno">   50</span><span class="comment"> *</span></div>
<div class="line"><a id="l00051" name="l00051"></a><span class="lineno">   51</span><span class="comment"> * One can either reserve to a specified service port (reserve_port()) or a random available</span></div>
<div class="line"><a id="l00052" name="l00052"></a><span class="lineno">   52</span><span class="comment"> * ephemeral port (reserve_ephemeral_port()).  Unlike with TCP and UDP ports, it&#39;s not possible to</span></div>
<div class="line"><a id="l00053" name="l00053"></a><span class="lineno">   53</span><span class="comment"> * reserve a user-supplied ephemeral port (reserve_port() will fail in this case).  Therefore,</span></div>
<div class="line"><a id="l00054" name="l00054"></a><span class="lineno">   54</span><span class="comment"> * service ports and ephemeral ports are entirely separate (it is not merely a convention as in TCP</span></div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno">   55</span><span class="comment"> * and UDP ports).</span></div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno">   56</span><span class="comment"> *</span></div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno">   57</span><span class="comment"> * While this is transparent to the class user, this implementation avoids reserving ephemeral ports</span></div>
<div class="line"><a id="l00058" name="l00058"></a><span class="lineno">   58</span><span class="comment"> * that have been recently returned, to avoid confusion in the socket implementation.  It does so by</span></div>
<div class="line"><a id="l00059" name="l00059"></a><span class="lineno">   59</span><span class="comment"> * keeping a queue (of some reasonably large length up to a maximum size) of such ports.  Ports</span></div>
<div class="line"><a id="l00060" name="l00060"></a><span class="lineno">   60</span><span class="comment"> * within this queue are reserved only if there is absolutely no ephemeral port space left other</span></div>
<div class="line"><a id="l00061" name="l00061"></a><span class="lineno">   61</span><span class="comment"> * than the ports on the queue.</span></div>
<div class="line"><a id="l00062" name="l00062"></a><span class="lineno">   62</span><span class="comment"> *</span></div>
<div class="line"><a id="l00063" name="l00063"></a><span class="lineno">   63</span><span class="comment"> * Main (all?) differences from TCP/UDP ports: different allocation of ephemeral vs. non-ephemeral</span></div>
<div class="line"><a id="l00064" name="l00064"></a><span class="lineno">   64</span><span class="comment"> * port space; no privileged ports; enforced inability to reserve a specific ephemeral port; no</span></div>
<div class="line"><a id="l00065" name="l00065"></a><span class="lineno">   65</span><span class="comment"> * service name -&gt; port number mapping (yet?).</span></div>
<div class="line"><a id="l00066" name="l00066"></a><span class="lineno">   66</span><span class="comment"> *</span></div>
<div class="line"><a id="l00067" name="l00067"></a><span class="lineno">   67</span><span class="comment"> * ### Thread safety ###</span></div>
<div class="line"><a id="l00068" name="l00068"></a><span class="lineno">   68</span><span class="comment"> * Separate objects: All functionality safe for simultaneous execution from multiple</span></div>
<div class="line"><a id="l00069" name="l00069"></a><span class="lineno">   69</span><span class="comment"> * threads.  Same object: Not safe to execute a non-const operation simultaneously with any other</span></div>
<div class="line"><a id="l00070" name="l00070"></a><span class="lineno">   70</span><span class="comment"> * operation; otherwise safe.  Rationale: Node only deals with its Port_space in thread W.</span></div>
<div class="line"><a id="l00071" name="l00071"></a><span class="lineno">   71</span><span class="comment"> *</span></div>
<div class="line"><a id="l00072" name="l00072"></a><span class="lineno">   72</span><span class="comment"> * ### Implementation notes ###</span></div>
<div class="line"><a id="l00073" name="l00073"></a><span class="lineno">   73</span><span class="comment"> * `bit_set` objects are used to represent the set of reserved vs. available ports of a</span></div>
<div class="line"><a id="l00074" name="l00074"></a><span class="lineno">   74</span><span class="comment"> * given type (0 means taken, 1 means available).  This is not only quick and memory-compact but</span></div>
<div class="line"><a id="l00075" name="l00075"></a><span class="lineno">   75</span><span class="comment"> * also allows a convenient search for a random available port (random bit -&gt; `find_next()` if not</span></div>
<div class="line"><a id="l00076" name="l00076"></a><span class="lineno">   76</span><span class="comment"> * open -&gt; `find_first()` if still not found -&gt; no ports available if even still not found).</span></div>
<div class="line"><a id="l00077" name="l00077"></a><span class="lineno">   77</span><span class="comment"> *</span></div>
<div class="line"><a id="l00078" name="l00078"></a><span class="lineno">   78</span><span class="comment"> * @todo While the ephemeral port reuse avoidance works well within a single Port_space lifetime,</span></div>
<div class="line"><a id="l00079" name="l00079"></a><span class="lineno">   79</span><span class="comment"> * it does not carry over across different Port_spaces.  I.e., if Port_space is destructed and then</span></div>
<div class="line"><a id="l00080" name="l00080"></a><span class="lineno">   80</span><span class="comment"> * constructed, the container of recently used ports starts out empty, so a port may (with some low</span></div>
<div class="line"><a id="l00081" name="l00081"></a><span class="lineno">   81</span><span class="comment"> * but sizable probability) be reused.  This could be avoided by persisting (e.g., via</span></div>
<div class="line"><a id="l00082" name="l00082"></a><span class="lineno">   82</span><span class="comment"> * boost.serialization) those structures to disk (perhaps at a user-supplied</span></div>
<div class="line"><a id="l00083" name="l00083"></a><span class="lineno">   83</span><span class="comment"> * `boost::filesystem::path`) in `~Port_space()`.  This wouldn&#39;t work if Port_space crashed, however.  To</span></div>
<div class="line"><a id="l00084" name="l00084"></a><span class="lineno">   84</span><span class="comment"> * solve that, we could easily start a thread in Port_space() (and join it in `~Port_space()`) that</span></div>
<div class="line"><a id="l00085" name="l00085"></a><span class="lineno">   85</span><span class="comment"> * would save that state every N seconds.  If that&#39;s not enough, we can instead have that thread run</span></div>
<div class="line"><a id="l00086" name="l00086"></a><span class="lineno">   86</span><span class="comment"> * a boost.asio `io_context::run()` event loop and `post(io_context&amp;)` the save operation onto it (from</span></div>
<div class="line"><a id="l00087" name="l00087"></a><span class="lineno">   87</span><span class="comment"> * arbitrary threads) each time a new ephemeral port is reserved (with some kind of protection</span></div>
<div class="line"><a id="l00088" name="l00088"></a><span class="lineno">   88</span><span class="comment"> * against incessant disk writing built into this worker thread; e.g., don&#39;t save if saved in the</span></div>
<div class="line"><a id="l00089" name="l00089"></a><span class="lineno">   89</span><span class="comment"> * last N msec).</span></div>
<div class="line"><a id="l00090" name="l00090"></a><span class="lineno">   90</span><span class="comment"> */</span></div>
<div class="line"><a id="l00091" name="l00091"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html">   91</a></span><span class="keyword">class </span><a class="code hl_class" href="classflow_1_1net__flow_1_1Port__space.html">Port_space</a> :</div>
<div class="line"><a id="l00092" name="l00092"></a><span class="lineno">   92</span>  <span class="keyword">public</span> <a class="code hl_class" href="classflow_1_1log_1_1Log__context.html">log::Log_context</a>,</div>
<div class="line"><a id="l00093" name="l00093"></a><span class="lineno">   93</span>  <span class="keyword">private</span> boost::noncopyable</div>
<div class="line"><a id="l00094" name="l00094"></a><span class="lineno">   94</span>{</div>
<div class="line"><a id="l00095" name="l00095"></a><span class="lineno">   95</span><span class="keyword">public</span>:</div>
<div class="line"><a id="l00096" name="l00096"></a><span class="lineno">   96</span>  <span class="comment">// Constants.</span></div>
<div class="line"><a id="l00097" name="l00097"></a><span class="lineno">   97</span><span class="comment"></span> </div>
<div class="line"><a id="l00098" name="l00098"></a><span class="lineno">   98</span><span class="comment">  /// Total number of ports in the port space, including #S_PORT_ANY.</span></div>
<div class="line"><a id="l00099" name="l00099"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#af0c60ec4732021d52a19e5d2f6dc8b35">   99</a></span><span class="comment"></span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">size_t</span> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#af0c60ec4732021d52a19e5d2f6dc8b35">S_NUM_PORTS</a>;</div>
<div class="line"><a id="l00100" name="l00100"></a><span class="lineno">  100</span><span class="comment"></span> </div>
<div class="line"><a id="l00101" name="l00101"></a><span class="lineno">  101</span><span class="comment">  /// Total number of &quot;service&quot; ports (ones that can be reserved by number with reserve_port()).</span></div>
<div class="line"><a id="l00102" name="l00102"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#ad93c0b6f23be37efe0f96ab066ff9bf8">  102</a></span><span class="comment"></span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">size_t</span> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#ad93c0b6f23be37efe0f96ab066ff9bf8">S_NUM_SERVICE_PORTS</a>;</div>
<div class="line"><a id="l00103" name="l00103"></a><span class="lineno">  103</span><span class="comment"></span> </div>
<div class="line"><a id="l00104" name="l00104"></a><span class="lineno">  104</span><span class="comment">  /// Total number of &quot;ephemeral&quot; ports (ones reserved at random with reserve_ephemeral_port()).</span></div>
<div class="line"><a id="l00105" name="l00105"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#a06fb009aafc77f75241f721734fe3cc4">  105</a></span><span class="comment"></span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">size_t</span> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#a06fb009aafc77f75241f721734fe3cc4">S_NUM_EPHEMERAL_PORTS</a>;</div>
<div class="line"><a id="l00106" name="l00106"></a><span class="lineno">  106</span><span class="comment"></span> </div>
<div class="line"><a id="l00107" name="l00107"></a><span class="lineno">  107</span><span class="comment">  /// The port number of the lowest service port.</span></div>
<div class="line"><a id="l00108" name="l00108"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#a6d07833521960b2f90806bfa7728cfd8">  108</a></span><span class="comment"></span>  <span class="keyword">static</span> <span class="keyword">const</span> <a class="code hl_typedef" href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow_port_t</a> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#a6d07833521960b2f90806bfa7728cfd8">S_FIRST_SERVICE_PORT</a>;</div>
<div class="line"><a id="l00109" name="l00109"></a><span class="lineno">  109</span><span class="comment"></span> </div>
<div class="line"><a id="l00110" name="l00110"></a><span class="lineno">  110</span><span class="comment">  /// The port number of the lowest ephemeral port.</span></div>
<div class="line"><a id="l00111" name="l00111"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#ab9a614b67638cbd9526eb82033a53352">  111</a></span><span class="comment"></span>  <span class="keyword">static</span> <span class="keyword">const</span> <a class="code hl_typedef" href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow_port_t</a> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#ab9a614b67638cbd9526eb82033a53352">S_FIRST_EPHEMERAL_PORT</a>;</div>
<div class="line"><a id="l00112" name="l00112"></a><span class="lineno">  112</span> </div>
<div class="line"><a id="l00113" name="l00113"></a><span class="lineno">  113</span>  <span class="comment">// Constructors/destructor.</span></div>
<div class="line"><a id="l00114" name="l00114"></a><span class="lineno">  114</span><span class="comment"></span> </div>
<div class="line"><a id="l00115" name="l00115"></a><span class="lineno">  115</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00116" name="l00116"></a><span class="lineno">  116</span><span class="comment">   * Constructs the Port_space with all ports available.</span></div>
<div class="line"><a id="l00117" name="l00117"></a><span class="lineno">  117</span><span class="comment">   *</span></div>
<div class="line"><a id="l00118" name="l00118"></a><span class="lineno">  118</span><span class="comment">   * @param logger</span></div>
<div class="line"><a id="l00119" name="l00119"></a><span class="lineno">  119</span><span class="comment">   *        The Logger implementation to use subsequently.</span></div>
<div class="line"><a id="l00120" name="l00120"></a><span class="lineno">  120</span><span class="comment">   */</span></div>
<div class="line"><a id="l00121" name="l00121"></a><span class="lineno">  121</span>  <span class="keyword">explicit</span> <a class="code hl_function" href="classflow_1_1net__flow_1_1Port__space.html#ad02a2c57aa6854659621af98b64d3638">Port_space</a>(<a class="code hl_class" href="classflow_1_1log_1_1Logger.html">log::Logger</a>* logger);</div>
<div class="line"><a id="l00122" name="l00122"></a><span class="lineno">  122</span> </div>
<div class="line"><a id="l00123" name="l00123"></a><span class="lineno">  123</span>  <span class="comment">// Methods.</span></div>
<div class="line"><a id="l00124" name="l00124"></a><span class="lineno">  124</span><span class="comment"></span> </div>
<div class="line"><a id="l00125" name="l00125"></a><span class="lineno">  125</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00126" name="l00126"></a><span class="lineno">  126</span><span class="comment">   * Reserve the specified service port, or reserve_ephemeral_port() if the specified port is</span></div>
<div class="line"><a id="l00127" name="l00127"></a><span class="lineno">  127</span><span class="comment">   * #S_PORT_ANY.</span></div>
<div class="line"><a id="l00128" name="l00128"></a><span class="lineno">  128</span><span class="comment">   *</span></div>
<div class="line"><a id="l00129" name="l00129"></a><span class="lineno">  129</span><span class="comment">   * @param port</span></div>
<div class="line"><a id="l00130" name="l00130"></a><span class="lineno">  130</span><span class="comment">   *        A valid and still available service port number, or #S_PORT_ANY.</span></div>
<div class="line"><a id="l00131" name="l00131"></a><span class="lineno">  131</span><span class="comment">   * @param err_code</span></div>
<div class="line"><a id="l00132" name="l00132"></a><span class="lineno">  132</span><span class="comment">   *        See flow::Error_code docs for error reporting semantics.  error::Code generated:</span></div>
<div class="line"><a id="l00133" name="l00133"></a><span class="lineno">  133</span><span class="comment">   *        error::Code::S_INVALID_SERVICE_PORT_NUMBER, error::Code::S_PORT_TAKEN, or</span></div>
<div class="line"><a id="l00134" name="l00134"></a><span class="lineno">  134</span><span class="comment">   *        whatever set by reserve_ephemeral_port() if `port == S_PORT_ANY`.</span></div>
<div class="line"><a id="l00135" name="l00135"></a><span class="lineno">  135</span><span class="comment">   * @return On success, the reserved port; on failure, #S_PORT_ANY.</span></div>
<div class="line"><a id="l00136" name="l00136"></a><span class="lineno">  136</span><span class="comment">   */</span></div>
<div class="line"><a id="l00137" name="l00137"></a><span class="lineno">  137</span>  <a class="code hl_typedef" href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow_port_t</a> <a class="code hl_function" href="classflow_1_1net__flow_1_1Port__space.html#a1168841ecd09d3187f9803eac2b8b703">reserve_port</a>(<a class="code hl_typedef" href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow_port_t</a> port, <a class="code hl_typedef" href="namespaceflow.html#a29eaaa9d0fac4ce87d8b969222dbed09">Error_code</a>* err_code);</div>
<div class="line"><a id="l00138" name="l00138"></a><span class="lineno">  138</span><span class="comment"></span> </div>
<div class="line"><a id="l00139" name="l00139"></a><span class="lineno">  139</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00140" name="l00140"></a><span class="lineno">  140</span><span class="comment">   * Reserve a randomly chosen available ephemeral port.</span></div>
<div class="line"><a id="l00141" name="l00141"></a><span class="lineno">  141</span><span class="comment">   *</span></div>
<div class="line"><a id="l00142" name="l00142"></a><span class="lineno">  142</span><span class="comment">   * @param err_code</span></div>
<div class="line"><a id="l00143" name="l00143"></a><span class="lineno">  143</span><span class="comment">   *        See flow::Error_code docs for error reporting semantics.  error::Code generated:</span></div>
<div class="line"><a id="l00144" name="l00144"></a><span class="lineno">  144</span><span class="comment">   *        error::Code::S_OUT_OF_PORTS.</span></div>
<div class="line"><a id="l00145" name="l00145"></a><span class="lineno">  145</span><span class="comment">   * @return On success, the reserved port; on failure, #S_PORT_ANY.</span></div>
<div class="line"><a id="l00146" name="l00146"></a><span class="lineno">  146</span><span class="comment">   */</span></div>
<div class="line"><a id="l00147" name="l00147"></a><span class="lineno">  147</span>  <a class="code hl_typedef" href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow_port_t</a> <a class="code hl_function" href="classflow_1_1net__flow_1_1Port__space.html#a65dbe99c7c4433e6c090f26c92ab3f78">reserve_ephemeral_port</a>(<a class="code hl_typedef" href="namespaceflow.html#a29eaaa9d0fac4ce87d8b969222dbed09">Error_code</a>* err_code);</div>
<div class="line"><a id="l00148" name="l00148"></a><span class="lineno">  148</span><span class="comment"></span> </div>
<div class="line"><a id="l00149" name="l00149"></a><span class="lineno">  149</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00150" name="l00150"></a><span class="lineno">  150</span><span class="comment">   * Return a previously reserved port (of any type).</span></div>
<div class="line"><a id="l00151" name="l00151"></a><span class="lineno">  151</span><span class="comment">   *</span></div>
<div class="line"><a id="l00152" name="l00152"></a><span class="lineno">  152</span><span class="comment">   * @param port</span></div>
<div class="line"><a id="l00153" name="l00153"></a><span class="lineno">  153</span><span class="comment">   *        A previously reserved port.</span></div>
<div class="line"><a id="l00154" name="l00154"></a><span class="lineno">  154</span><span class="comment">   * @param err_code</span></div>
<div class="line"><a id="l00155" name="l00155"></a><span class="lineno">  155</span><span class="comment">   *        See flow::Error_code docs for error reporting semantics.  error::Code generated:</span></div>
<div class="line"><a id="l00156" name="l00156"></a><span class="lineno">  156</span><span class="comment">   *        error::Code::S_PORT_TAKEN.</span></div>
<div class="line"><a id="l00157" name="l00157"></a><span class="lineno">  157</span><span class="comment">   */</span></div>
<div class="line"><a id="l00158" name="l00158"></a><span class="lineno">  158</span>  <span class="keywordtype">void</span> <a class="code hl_function" href="classflow_1_1net__flow_1_1Port__space.html#a9fe1be917ff7584ff587b5da5967127a">return_port</a>(<a class="code hl_typedef" href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow_port_t</a> port, <a class="code hl_typedef" href="namespaceflow.html#a29eaaa9d0fac4ce87d8b969222dbed09">Error_code</a>* err_code);</div>
<div class="line"><a id="l00159" name="l00159"></a><span class="lineno">  159</span> </div>
<div class="line"><a id="l00160" name="l00160"></a><span class="lineno">  160</span><span class="keyword">private</span>:</div>
<div class="line"><a id="l00161" name="l00161"></a><span class="lineno">  161</span>  <span class="comment">// Types.</span></div>
<div class="line"><a id="l00162" name="l00162"></a><span class="lineno">  162</span><span class="comment"></span> </div>
<div class="line"><a id="l00163" name="l00163"></a><span class="lineno">  163</span><span class="comment">  /// Short-hand for bit set of arbitary length, representing a port set (each bit is a port; 1 open, 0 reserved).</span></div>
<div class="line"><a id="l00164" name="l00164"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#a729dc0add1c98ebde5b3549d3ec132e2">  164</a></span><span class="comment"></span>  <span class="keyword">using </span><a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#a729dc0add1c98ebde5b3549d3ec132e2">Bit_set</a> = boost::dynamic_bitset&lt;&gt;;</div>
<div class="line"><a id="l00165" name="l00165"></a><span class="lineno">  165</span><span class="comment"></span> </div>
<div class="line"><a id="l00166" name="l00166"></a><span class="lineno">  166</span><span class="comment">  /// Random number generator.</span></div>
<div class="line"><a id="l00167" name="l00167"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#af4690f25a42ebb61561f91c9187bcc30">  167</a></span><span class="comment"></span>  <span class="keyword">using </span><a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#af4690f25a42ebb61561f91c9187bcc30">Random_generator</a> = <a class="code hl_typedef" href="classflow_1_1util_1_1Rnd__gen__uniform__range__base.html#a519fc83fd1c52a82618cd85f3a089668">util::Rnd_gen_uniform_range_base::Random_generator</a>;</div>
<div class="line"><a id="l00168" name="l00168"></a><span class="lineno">  168</span><span class="comment"></span> </div>
<div class="line"><a id="l00169" name="l00169"></a><span class="lineno">  169</span><span class="comment">  /// A type same as #flow_port_t but larger, useful when doing arithmetic that might hit overflow in corner cases.</span></div>
<div class="line"><a id="l00170" name="l00170"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#afb17ac5ea9708262d0c374dc246a7244">  170</a></span><span class="comment"></span>  <span class="keyword">using </span><a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#afb17ac5ea9708262d0c374dc246a7244">flow_port_sans_overflow_t</a> = uint32_t;</div>
<div class="line"><a id="l00171" name="l00171"></a><span class="lineno">  171</span> </div>
<div class="line"><a id="l00172" name="l00172"></a><span class="lineno">  172</span>  <span class="comment">// Type checks.</span></div>
<div class="line"><a id="l00173" name="l00173"></a><span class="lineno">  173</span>  <span class="keyword">static_assert</span>((std::numeric_limits&lt;flow_port_sans_overflow_t&gt;::is_integer <span class="comment">// Mostly silly sanity checks....</span></div>
<div class="line"><a id="l00174" name="l00174"></a><span class="lineno">  174</span>                   == std::numeric_limits&lt;flow_port_t&gt;::is_integer)</div>
<div class="line"><a id="l00175" name="l00175"></a><span class="lineno">  175</span>                  &amp;&amp; (std::numeric_limits&lt;flow_port_sans_overflow_t&gt;::is_signed</div>
<div class="line"><a id="l00176" name="l00176"></a><span class="lineno">  176</span>                        == std::numeric_limits&lt;flow_port_t&gt;::is_signed)</div>
<div class="line"><a id="l00177" name="l00177"></a><span class="lineno">  177</span>                  &amp;&amp; (<span class="keyword">sizeof</span>(<a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#afb17ac5ea9708262d0c374dc246a7244">flow_port_sans_overflow_t</a>) &gt; <span class="keyword">sizeof</span>(<a class="code hl_typedef" href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow_port_t</a>)), <span class="comment">// ...but main point is here.</span></div>
<div class="line"><a id="l00178" name="l00178"></a><span class="lineno">  178</span>                <span class="stringliteral">&quot;flow_port_sans_overflow_t must be similar to flow_port_t but with larger max value.&quot;</span>);</div>
<div class="line"><a id="l00179" name="l00179"></a><span class="lineno">  179</span> </div>
<div class="line"><a id="l00180" name="l00180"></a><span class="lineno">  180</span>  <span class="comment">// Methods.</span></div>
<div class="line"><a id="l00181" name="l00181"></a><span class="lineno">  181</span><span class="comment"></span> </div>
<div class="line"><a id="l00182" name="l00182"></a><span class="lineno">  182</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00183" name="l00183"></a><span class="lineno">  183</span><span class="comment">   * Returns `true` if and only if the given port is a service port (as opposed to ephemeral or</span></div>
<div class="line"><a id="l00184" name="l00184"></a><span class="lineno">  184</span><span class="comment">   * #S_PORT_ANY).</span></div>
<div class="line"><a id="l00185" name="l00185"></a><span class="lineno">  185</span><span class="comment">   *</span></div>
<div class="line"><a id="l00186" name="l00186"></a><span class="lineno">  186</span><span class="comment">   * @param port</span></div>
<div class="line"><a id="l00187" name="l00187"></a><span class="lineno">  187</span><span class="comment">   *        Port to check.</span></div>
<div class="line"><a id="l00188" name="l00188"></a><span class="lineno">  188</span><span class="comment">   * @return See above.</span></div>
<div class="line"><a id="l00189" name="l00189"></a><span class="lineno">  189</span><span class="comment">   */</span></div>
<div class="line"><a id="l00190" name="l00190"></a><span class="lineno">  190</span>  <span class="keyword">static</span> <span class="keywordtype">bool</span> <a class="code hl_function" href="classflow_1_1net__flow_1_1Port__space.html#ac43e4303aac2bde697b99bf03901ec85">is_service_port</a>(<a class="code hl_typedef" href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow_port_t</a> port);</div>
<div class="line"><a id="l00191" name="l00191"></a><span class="lineno">  191</span><span class="comment"></span> </div>
<div class="line"><a id="l00192" name="l00192"></a><span class="lineno">  192</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00193" name="l00193"></a><span class="lineno">  193</span><span class="comment">   * Helper method that, given a reference to a bit set representing available ports (1 available, 0</span></div>
<div class="line"><a id="l00194" name="l00194"></a><span class="lineno">  194</span><span class="comment">   * reserved) finds a random available (1) port in that bit set.</span></div>
<div class="line"><a id="l00195" name="l00195"></a><span class="lineno">  195</span><span class="comment">   *</span></div>
<div class="line"><a id="l00196" name="l00196"></a><span class="lineno">  196</span><span class="comment">   * @param ports</span></div>
<div class="line"><a id="l00197" name="l00197"></a><span class="lineno">  197</span><span class="comment">   *        A bit set representing port availability (e.g., #m_ephemeral_ports).</span></div>
<div class="line"><a id="l00198" name="l00198"></a><span class="lineno">  198</span><span class="comment">   * @return The bit index of a random available port, or `Bit_set::npos` if all are taken.</span></div>
<div class="line"><a id="l00199" name="l00199"></a><span class="lineno">  199</span><span class="comment">   */</span></div>
<div class="line"><a id="l00200" name="l00200"></a><span class="lineno">  200</span>  <span class="keywordtype">size_t</span> <a class="code hl_function" href="classflow_1_1net__flow_1_1Port__space.html#ad5a6a34a24c95364bb8348e5030d955b">find_available_port_bit_idx</a>(<span class="keyword">const</span> <a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#a729dc0add1c98ebde5b3549d3ec132e2">Bit_set</a>&amp; ports);</div>
<div class="line"><a id="l00201" name="l00201"></a><span class="lineno">  201</span> </div>
<div class="line"><a id="l00202" name="l00202"></a><span class="lineno">  202</span>  <span class="comment">// Constants.</span></div>
<div class="line"><a id="l00203" name="l00203"></a><span class="lineno">  203</span><span class="comment"></span> </div>
<div class="line"><a id="l00204" name="l00204"></a><span class="lineno">  204</span><span class="comment">  /// The maximum size of #m_recent_ephemeral_ports.</span></div>
<div class="line"><a id="l00205" name="l00205"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#a0bdaf744b7089027c8d952b67d1f9cc0">  205</a></span><span class="comment"></span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">size_t</span> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#a0bdaf744b7089027c8d952b67d1f9cc0">S_MAX_RECENT_EPHEMERAL_PORTS</a>;</div>
<div class="line"><a id="l00206" name="l00206"></a><span class="lineno">  206</span> </div>
<div class="line"><a id="l00207" name="l00207"></a><span class="lineno">  207</span>  <span class="comment">// Data.</span></div>
<div class="line"><a id="l00208" name="l00208"></a><span class="lineno">  208</span><span class="comment"></span> </div>
<div class="line"><a id="l00209" name="l00209"></a><span class="lineno">  209</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00210" name="l00210"></a><span class="lineno">  210</span><span class="comment">   * Current service port set.  Bit 0 is port #S_FIRST_SERVICE_PORT, bit 1 is `S_FIRST_SERVICE_PORT + 1`,</span></div>
<div class="line"><a id="l00211" name="l00211"></a><span class="lineno">  211</span><span class="comment">   * etc.  In particular, this starts off as all 1s (all ports open).</span></div>
<div class="line"><a id="l00212" name="l00212"></a><span class="lineno">  212</span><span class="comment">   */</span></div>
<div class="line"><a id="l00213" name="l00213"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#a1f8e8e52bf4ec90e0b13d9159c403eae">  213</a></span>  <a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#a729dc0add1c98ebde5b3549d3ec132e2">Bit_set</a> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#a1f8e8e52bf4ec90e0b13d9159c403eae">m_service_ports</a>;</div>
<div class="line"><a id="l00214" name="l00214"></a><span class="lineno">  214</span><span class="comment"></span> </div>
<div class="line"><a id="l00215" name="l00215"></a><span class="lineno">  215</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00216" name="l00216"></a><span class="lineno">  216</span><span class="comment">   * Current ephemeral port set; indexing analogous to #m_service_ports but starting at</span></div>
<div class="line"><a id="l00217" name="l00217"></a><span class="lineno">  217</span><span class="comment">   * #S_FIRST_EPHEMERAL_PORT.</span></div>
<div class="line"><a id="l00218" name="l00218"></a><span class="lineno">  218</span><span class="comment">   */</span></div>
<div class="line"><a id="l00219" name="l00219"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#aeafab53f020093121f5e57f1e692a9df">  219</a></span>  <a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#a729dc0add1c98ebde5b3549d3ec132e2">Bit_set</a> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#aeafab53f020093121f5e57f1e692a9df">m_ephemeral_ports</a>;</div>
<div class="line"><a id="l00220" name="l00220"></a><span class="lineno">  220</span><span class="comment"></span> </div>
<div class="line"><a id="l00221" name="l00221"></a><span class="lineno">  221</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00222" name="l00222"></a><span class="lineno">  222</span><span class="comment">   * Set representing the union of the set of current reserved ephemeral ports and the set of the</span></div>
<div class="line"><a id="l00223" name="l00223"></a><span class="lineno">  223</span><span class="comment">   * last up-to-#S_MAX_RECENT_EPHEMERAL_PORTS returned and available ephemeral ports.  In other</span></div>
<div class="line"><a id="l00224" name="l00224"></a><span class="lineno">  224</span><span class="comment">   * words, the union of the ports represented by #m_ephemeral_ports and #m_recent_ephemeral_ports.</span></div>
<div class="line"><a id="l00225" name="l00225"></a><span class="lineno">  225</span><span class="comment">   * In yet other words, a 1 bit represents an available and not-recently-used port.  This is kept</span></div>
<div class="line"><a id="l00226" name="l00226"></a><span class="lineno">  226</span><span class="comment">   * for performance, so that when choosing a random port one can find a random 1 bit to find a</span></div>
<div class="line"><a id="l00227" name="l00227"></a><span class="lineno">  227</span><span class="comment">   * not-recently-used and open port.</span></div>
<div class="line"><a id="l00228" name="l00228"></a><span class="lineno">  228</span><span class="comment">   *</span></div>
<div class="line"><a id="l00229" name="l00229"></a><span class="lineno">  229</span><span class="comment">   * Invariants:</span></div>
<div class="line"><a id="l00230" name="l00230"></a><span class="lineno">  230</span><span class="comment">   *   - Port `P` is in #m_recent_ephemeral_ports =&gt; bit `(P - S_FIRST_EPHEMERAL_PORT)` is 0 in this.</span></div>
<div class="line"><a id="l00231" name="l00231"></a><span class="lineno">  231</span><span class="comment">   *   - Bit `N` is 0 in #m_ephemeral_ports =&gt; bit `N` is 0 in this.</span></div>
<div class="line"><a id="l00232" name="l00232"></a><span class="lineno">  232</span><span class="comment">   *   - All other bits are 1.</span></div>
<div class="line"><a id="l00233" name="l00233"></a><span class="lineno">  233</span><span class="comment">   */</span></div>
<div class="line"><a id="l00234" name="l00234"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#abc455d9e1b00886f7985c7b5fd115862">  234</a></span>  <a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#a729dc0add1c98ebde5b3549d3ec132e2">Bit_set</a> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#abc455d9e1b00886f7985c7b5fd115862">m_ephemeral_and_recent_ephemeral_ports</a>;</div>
<div class="line"><a id="l00235" name="l00235"></a><span class="lineno">  235</span><span class="comment"></span> </div>
<div class="line"><a id="l00236" name="l00236"></a><span class="lineno">  236</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00237" name="l00237"></a><span class="lineno">  237</span><span class="comment">   * A FIFO of recently used but currently available ephemeral ports.  Algorithm: push port onto</span></div>
<div class="line"><a id="l00238" name="l00238"></a><span class="lineno">  238</span><span class="comment">   * back of queue when it&#39;s returned; pop front of queue if #m_recent_ephemeral_ports is beyond</span></div>
<div class="line"><a id="l00239" name="l00239"></a><span class="lineno">  239</span><span class="comment">   * #S_MAX_RECENT_EPHEMERAL_PORTS long.  If port is needed and no more</span></div>
<div class="line"><a id="l00240" name="l00240"></a><span class="lineno">  240</span><span class="comment">   * non-#m_ephemeral_and_recent_ephemeral_ports ports are available, pop front of queue (i.e.,</span></div>
<div class="line"><a id="l00241" name="l00241"></a><span class="lineno">  241</span><span class="comment">   * oldest recently used port) and use that.  If emptied, there are simply no more ports left.</span></div>
<div class="line"><a id="l00242" name="l00242"></a><span class="lineno">  242</span><span class="comment">   */</span></div>
<div class="line"><a id="l00243" name="l00243"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#ae401e02d49ce557bbc5474e049eb5455">  243</a></span>  std::queue&lt;flow_port_t&gt; <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#ae401e02d49ce557bbc5474e049eb5455">m_recent_ephemeral_ports</a>;</div>
<div class="line"><a id="l00244" name="l00244"></a><span class="lineno">  244</span><span class="comment"></span> </div>
<div class="line"><a id="l00245" name="l00245"></a><span class="lineno">  245</span><span class="comment">  /// Random number generator for picking ports.</span></div>
<div class="line"><a id="l00246" name="l00246"></a><span class="lineno"><a class="line" href="classflow_1_1net__flow_1_1Port__space.html#ae4714945b23e588b1554240fa590560a">  246</a></span><span class="comment"></span>  <a class="code hl_typedef" href="classflow_1_1net__flow_1_1Port__space.html#af4690f25a42ebb61561f91c9187bcc30">Random_generator</a> <a class="code hl_variable" href="classflow_1_1net__flow_1_1Port__space.html#ae4714945b23e588b1554240fa590560a">m_rnd_generator</a>;</div>
<div class="line"><a id="l00247" name="l00247"></a><span class="lineno">  247</span>}; <span class="comment">// class Port_space</span></div>
<div class="line"><a id="l00248" name="l00248"></a><span class="lineno">  248</span> </div>
<div class="line"><a id="l00249" name="l00249"></a><span class="lineno">  249</span>} <span class="comment">// namespace flow::net_flow</span></div>
<div class="ttc" id="aclassflow_1_1log_1_1Log__context_html"><div class="ttname"><a href="classflow_1_1log_1_1Log__context.html">flow::log::Log_context</a></div><div class="ttdoc">Convenience class that simply stores a Logger and/or Component passed into a constructor; and returns...</div><div class="ttdef"><b>Definition:</b> <a href="log_8hpp_source.html#l01609">log.hpp:1610</a></div></div>
<div class="ttc" id="aclassflow_1_1log_1_1Logger_html"><div class="ttname"><a href="classflow_1_1log_1_1Logger.html">flow::log::Logger</a></div><div class="ttdoc">Interface that the user should implement, passing the implementing Logger into logging classes (Flow'...</div><div class="ttdef"><b>Definition:</b> <a href="log_8hpp_source.html#l01280">log.hpp:1284</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html">flow::net_flow::Port_space</a></div><div class="ttdoc">Internal net_flow class that maintains the available Flow-protocol port space, somewhat similarly to ...</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00091">port_space.hpp:94</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_a06fb009aafc77f75241f721734fe3cc4"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#a06fb009aafc77f75241f721734fe3cc4">flow::net_flow::Port_space::S_NUM_EPHEMERAL_PORTS</a></div><div class="ttdeci">static const size_t S_NUM_EPHEMERAL_PORTS</div><div class="ttdoc">Total number of &quot;ephemeral&quot; ports (ones reserved at random with reserve_ephemeral_port()).</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00105">port_space.hpp:105</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_a0bdaf744b7089027c8d952b67d1f9cc0"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#a0bdaf744b7089027c8d952b67d1f9cc0">flow::net_flow::Port_space::S_MAX_RECENT_EPHEMERAL_PORTS</a></div><div class="ttdeci">static const size_t S_MAX_RECENT_EPHEMERAL_PORTS</div><div class="ttdoc">The maximum size of m_recent_ephemeral_ports.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00205">port_space.hpp:205</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_a1168841ecd09d3187f9803eac2b8b703"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#a1168841ecd09d3187f9803eac2b8b703">flow::net_flow::Port_space::reserve_port</a></div><div class="ttdeci">flow_port_t reserve_port(flow_port_t port, Error_code *err_code)</div><div class="ttdoc">Reserve the specified service port, or reserve_ephemeral_port() if the specified port is S_PORT_ANY.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8cpp_source.html#l00075">port_space.cpp:75</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_a1f8e8e52bf4ec90e0b13d9159c403eae"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#a1f8e8e52bf4ec90e0b13d9159c403eae">flow::net_flow::Port_space::m_service_ports</a></div><div class="ttdeci">Bit_set m_service_ports</div><div class="ttdoc">Current service port set.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00213">port_space.hpp:213</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_a65dbe99c7c4433e6c090f26c92ab3f78"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#a65dbe99c7c4433e6c090f26c92ab3f78">flow::net_flow::Port_space::reserve_ephemeral_port</a></div><div class="ttdeci">flow_port_t reserve_ephemeral_port(Error_code *err_code)</div><div class="ttdoc">Reserve a randomly chosen available ephemeral port.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8cpp_source.html#l00112">port_space.cpp:112</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_a6d07833521960b2f90806bfa7728cfd8"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#a6d07833521960b2f90806bfa7728cfd8">flow::net_flow::Port_space::S_FIRST_SERVICE_PORT</a></div><div class="ttdeci">static const flow_port_t S_FIRST_SERVICE_PORT</div><div class="ttdoc">The port number of the lowest service port.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00108">port_space.hpp:108</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_a729dc0add1c98ebde5b3549d3ec132e2"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#a729dc0add1c98ebde5b3549d3ec132e2">flow::net_flow::Port_space::Bit_set</a></div><div class="ttdeci">boost::dynamic_bitset&lt;&gt; Bit_set</div><div class="ttdoc">Short-hand for bit set of arbitary length, representing a port set (each bit is a port; 1 open,...</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00164">port_space.hpp:164</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_a9fe1be917ff7584ff587b5da5967127a"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#a9fe1be917ff7584ff587b5da5967127a">flow::net_flow::Port_space::return_port</a></div><div class="ttdeci">void return_port(flow_port_t port, Error_code *err_code)</div><div class="ttdoc">Return a previously reserved port (of any type).</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8cpp_source.html#l00175">port_space.cpp:175</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_ab9a614b67638cbd9526eb82033a53352"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#ab9a614b67638cbd9526eb82033a53352">flow::net_flow::Port_space::S_FIRST_EPHEMERAL_PORT</a></div><div class="ttdeci">static const flow_port_t S_FIRST_EPHEMERAL_PORT</div><div class="ttdoc">The port number of the lowest ephemeral port.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00111">port_space.hpp:111</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_abc455d9e1b00886f7985c7b5fd115862"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#abc455d9e1b00886f7985c7b5fd115862">flow::net_flow::Port_space::m_ephemeral_and_recent_ephemeral_ports</a></div><div class="ttdeci">Bit_set m_ephemeral_and_recent_ephemeral_ports</div><div class="ttdoc">Set representing the union of the set of current reserved ephemeral ports and the set of the last up-...</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00234">port_space.hpp:234</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_ac43e4303aac2bde697b99bf03901ec85"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#ac43e4303aac2bde697b99bf03901ec85">flow::net_flow::Port_space::is_service_port</a></div><div class="ttdeci">static bool is_service_port(flow_port_t port)</div><div class="ttdoc">Returns true if and only if the given port is a service port (as opposed to ephemeral or S_PORT_ANY).</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8cpp_source.html#l00067">port_space.cpp:67</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_ad02a2c57aa6854659621af98b64d3638"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#ad02a2c57aa6854659621af98b64d3638">flow::net_flow::Port_space::Port_space</a></div><div class="ttdeci">Port_space(log::Logger *logger)</div><div class="ttdoc">Constructs the Port_space with all ports available.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8cpp_source.html#l00045">port_space.cpp:45</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_ad5a6a34a24c95364bb8348e5030d955b"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#ad5a6a34a24c95364bb8348e5030d955b">flow::net_flow::Port_space::find_available_port_bit_idx</a></div><div class="ttdeci">size_t find_available_port_bit_idx(const Bit_set &amp;ports)</div><div class="ttdoc">Helper method that, given a reference to a bit set representing available ports (1 available,...</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8cpp_source.html#l00261">port_space.cpp:261</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_ad93c0b6f23be37efe0f96ab066ff9bf8"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#ad93c0b6f23be37efe0f96ab066ff9bf8">flow::net_flow::Port_space::S_NUM_SERVICE_PORTS</a></div><div class="ttdeci">static const size_t S_NUM_SERVICE_PORTS</div><div class="ttdoc">Total number of &quot;service&quot; ports (ones that can be reserved by number with reserve_port()).</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00102">port_space.hpp:102</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_ae401e02d49ce557bbc5474e049eb5455"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#ae401e02d49ce557bbc5474e049eb5455">flow::net_flow::Port_space::m_recent_ephemeral_ports</a></div><div class="ttdeci">std::queue&lt; flow_port_t &gt; m_recent_ephemeral_ports</div><div class="ttdoc">A FIFO of recently used but currently available ephemeral ports.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00243">port_space.hpp:243</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_ae4714945b23e588b1554240fa590560a"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#ae4714945b23e588b1554240fa590560a">flow::net_flow::Port_space::m_rnd_generator</a></div><div class="ttdeci">Random_generator m_rnd_generator</div><div class="ttdoc">Random number generator for picking ports.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00246">port_space.hpp:246</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_aeafab53f020093121f5e57f1e692a9df"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#aeafab53f020093121f5e57f1e692a9df">flow::net_flow::Port_space::m_ephemeral_ports</a></div><div class="ttdeci">Bit_set m_ephemeral_ports</div><div class="ttdoc">Current ephemeral port set; indexing analogous to m_service_ports but starting at S_FIRST_EPHEMERAL_P...</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00219">port_space.hpp:219</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_af0c60ec4732021d52a19e5d2f6dc8b35"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#af0c60ec4732021d52a19e5d2f6dc8b35">flow::net_flow::Port_space::S_NUM_PORTS</a></div><div class="ttdeci">static const size_t S_NUM_PORTS</div><div class="ttdoc">Total number of ports in the port space, including S_PORT_ANY.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00099">port_space.hpp:99</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_af4690f25a42ebb61561f91c9187bcc30"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#af4690f25a42ebb61561f91c9187bcc30">flow::net_flow::Port_space::Random_generator</a></div><div class="ttdeci">util::Rnd_gen_uniform_range_base::Random_generator Random_generator</div><div class="ttdoc">Random number generator.</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00167">port_space.hpp:167</a></div></div>
<div class="ttc" id="aclassflow_1_1net__flow_1_1Port__space_html_afb17ac5ea9708262d0c374dc246a7244"><div class="ttname"><a href="classflow_1_1net__flow_1_1Port__space.html#afb17ac5ea9708262d0c374dc246a7244">flow::net_flow::Port_space::flow_port_sans_overflow_t</a></div><div class="ttdeci">uint32_t flow_port_sans_overflow_t</div><div class="ttdoc">A type same as flow_port_t but larger, useful when doing arithmetic that might hit overflow in corner...</div><div class="ttdef"><b>Definition:</b> <a href="port__space_8hpp_source.html#l00170">port_space.hpp:170</a></div></div>
<div class="ttc" id="aclassflow_1_1util_1_1Rnd__gen__uniform__range__base_html_a519fc83fd1c52a82618cd85f3a089668"><div class="ttname"><a href="classflow_1_1util_1_1Rnd__gen__uniform__range__base.html#a519fc83fd1c52a82618cd85f3a089668">flow::util::Rnd_gen_uniform_range_base::Random_generator</a></div><div class="ttdeci">boost::random::mt19937 Random_generator</div><div class="ttdoc">The random generator engine; it is public for the reason explained in Usability section of the Rnd_ge...</div><div class="ttdef"><b>Definition:</b> <a href="random_8hpp_source.html#l00041">random.hpp:41</a></div></div>
<div class="ttc" id="adetail_2net__flow__fwd_8hpp_html"><div class="ttname"><a href="detail_2net__flow__fwd_8hpp.html">net_flow_fwd.hpp</a></div></div>
<div class="ttc" id="alog_8hpp_html"><div class="ttname"><a href="log_8hpp.html">log.hpp</a></div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_html"><div class="ttname"><a href="namespaceflow_1_1net__flow.html">flow::net_flow</a></div><div class="ttdoc">Flow module containing the API and implementation of the Flow network protocol, a TCP-inspired stream...</div><div class="ttdef"><b>Definition:</b> <a href="asio_2node_8cpp_source.html#l00024">node.cpp:25</a></div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_html_a079d8cd87a68d1c5f04c6bce71f0061d"><div class="ttname"><a href="namespaceflow_1_1net__flow.html#a079d8cd87a68d1c5f04c6bce71f0061d">flow::net_flow::flow_port_t</a></div><div class="ttdeci">uint16_t flow_port_t</div><div class="ttdoc">Logical Flow port type (analogous to a UDP/TCP port in spirit but in no way relevant to UDP/TCP).</div><div class="ttdef"><b>Definition:</b> <a href="net__flow__fwd_8hpp_source.html#l00054">net_flow_fwd.hpp:54</a></div></div>
<div class="ttc" id="anamespaceflow_html_a29eaaa9d0fac4ce87d8b969222dbed09"><div class="ttname"><a href="namespaceflow.html#a29eaaa9d0fac4ce87d8b969222dbed09">flow::Error_code</a></div><div class="ttdeci">boost::system::error_code Error_code</div><div class="ttdoc">Short-hand for a boost.system error code (which basically encapsulates an integer/enum error code and...</div><div class="ttdef"><b>Definition:</b> <a href="common_8hpp_source.html#l00508">common.hpp:508</a></div></div>
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